In recent years, life prognosis of patients has significantly improved for carcinoma such as gastric cancer or colon cancer that can be discovered early and resected. However, pancreatic cancer, gallbladder cancer, lung cancer and the like are often discovered as advanced cancer. In addition, chemotherapy and radiation therapy, which have significant side effects and impair QOL, are concurrently used in some cases such that the prognosis is not considered as clearly improved (National Cancer Center Japan, Monitoring of Cancer Incidence in Japan—Survival 2000-2002 report).
With westernization of diet in recent years, cancer found frequently in the West, such as colon cancer, breast cancer, lung cancer, and prostate cancer, is increasing instead of gastric cancer. The follow-up study of about 40,000 males and females between 40 to 69 years of age in 9 regions from year 1990 to 2003 by the research team of the Ministry of Health, Labour and Welfare has reported a result showing that males with a high C peptide value is as much as 3-times more likely to suffer from colon cancer than males with a low value. (Non-Patent Literature 1=Int J Cancer. 2007 May 1; 120(9): 2007-12).